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On the basis of these clinical findings, a differential diagnosis of Oculocutaneous Albinism with Squamous Cell Carcinoma (SCC)/ Basal Cell Carcinoma (BCC)/ Malignant Melanoma (MM) was made. Routine haematological and biochemical investigations were normal. Chest X-Ray and Ultrasound Abdomen did not reveal any abnormalities. Biopsy from the ulcerated plaque showed features of well differentiated squamous cell carcinoma (Fig. 5). Wide surgical excision was done in this patient and counselled regarding photoprotection. He is under long term follow-up for recurrences. Figure 1. Generalized depigmented skin with white hairs, brownish freckles and telangiectasia Discussion Oculocutaneous albinism (OCA) is a group of four autosomal recessive disorders caused by either a complete lack or a reduction of melanin biosynthesis in the melanocytes resulting in hypopigmentation of the hair, skin and eyes. Reduction of melanin in the eyes results in reduced visual acuity caused by foveal hypoplasia and misrouting of the optic nerve fibres. Figure 2 and 3. Depigmentation with brownish freckles and telangiectasia over the chest and back Figure 4A. Ulcerated plaque with crusting and rolled out edges on the right wrist. B. Close-up view of the ulcerated plaque © Our Dermatol Online 2.2013 209
Figure 5. Invasive neoplastic cells with keratin pearl formation (H&E, 10x) The clinical spectrum of OCA varies, with OCA1A being the most severe type characterized by a complete lack of melanin production throughout life, while the milder forms OCA1B, OCA2, OCA3 and OCA4 show some pigment accumulation over time. The different types of OCA are caused by mutations in different genes but the clinical phenotype is not always distinguishable, making molecular diagnosis a useful tool and essential for genetic counseling [7]. Albinism can affect people of all ethnic backgrounds and has been extensively studied. Approximately one in 17,000 people have one of the types of albinism [8]. This suggests that about 1 in 70 people carry a gene for OCA [7]. Prevalence of the different forms of albinism varies considerably worldwide, partly explained by the different founder mutations in different genes and the fact that it can be difficult clinically to distinguish between the different subtypes of albinism among the large normal spectrum of pigmentation. OCA2 is the most prevalent form worldwide [9]. OCA1 is caused by mutations in the tyrosinase gene on chromosome 11q14.3 [10]. Mutations completely abolishing tyrosinase activity result in OCA1A, while mutations rendering some enzyme activity result in OCA1B allowing some accumulation of melanin pigment over time. Mutations in the OCA2 gene (formerly known as the P-gene) cause the OCA2 phenotype [11]. All types of OCA and ocular albinism (OA) have similar ocular findings, including various degrees of congenital nystagmus, hypopigmentation of iris leading to iris translucency, reduced pigmentation of the retinal pigment epithelium, foveal hypoplasia, reduced visual acuity usually in the range 20/60 to 20/400 and refractive errors, and sometimes a degree of color vision impairment [8,12]. Photophobia may be prominent. A characteristic finding is misrouting of the optic nerves, consisting in an excessive crossing of the fibres in the optic chiasma, which can result in strabismus and reduced stereoscopic vision [13]. Absence of misrouting excludes the diagnosis of albinism. The degree of skin and hair hypopigmentation varies with the type of albinism but is in general reduced [12]. In OCA1A the hair, eyelashes and eyebrows are white, and the skin is white and does not tan. Irises are light blue to almost pink, and fully translucent. Pigment does not develop and amelanotic nevi may be present. The symptoms do not vary with age or race. Visual acuity is 1/10 or less, and photophobia is intense. In OCA1B, the hair and skin may develop some pigment with time (after 1 to 3 years), and blue irises may change to green/brown. Visual acuity is 2/10. This phenotype was previously known as yellow albinism. In OCA2, the amount of cutaneous pigment may vary, and newborn nearly always have pigmented hair. Nevi and ephelids are common. Iris color varies and the pink eyes seen in OCA1A are usually absent. Visual acuity is usually better than in OCA1, and can reach 3/10 [7]. The diagnosis of OCA is based on clinical findings of hypopigmentation of the skin and hair, in addition to the characteristic ocular symptoms. However, due to the clinical overlap between the OCA subtypes, molecular diagnosis is necessary in order to establish the gene defect and thus the OCA subtype. Molecular genetic testing is based on mutational analysis of the genes, by standard screening methods such as denaturing high performance liquid chromatography (DHPLC) or single stranded conformational polymorphism (SSCP), followed by DNA sequencing [7]. The parents of an affected child are obligate carriers, the recurrence risk for another affected child is 25%, and healthy sibs are at 67% risk of being carriers. Offspring of an affected person are obligate carriers. Carriers are asymptomatic. Prenatal diagnosis can be done on DNA extracted from chorion villus sampling (CVS) at 10–12 weeks gestation or on DNA extracted from cultured amniocytes [7]. Prenatal diagnosis has been performed on skin biopsies from the fetus [14]. Skin cancers are generally commoner in the middle aged and elderly. In albinos however these cancers are known to present earlier [15-17]. Most important risk factor for the development of SCC is environmental exposure to ultraviolet light, as evidenced by increased incidence in sunnier climates, lower rates in dark skin & majority arising over sun-exposed skin. Melanin is a photo protective pigment, protecting the skin from the harmful effects of ultraviolet radiation. Its deficiency in people with albinism predisposes them to the harmful effects of ultraviolet radiation exposure, resulting in issues such as photophobia, decreased visual acuity, extreme sun sensitivity, and skin cancers [18]. High levels of exposure to ultraviolet radiation increase the risk of all three major forms of skin cancer and are responsible for the anatomical site distribution [19]. No use of protection for the skin increased the risk of skin cancer in these patients. Kromberg et al. reported that 23.4% of albinos developed skin cancer out of 111 albinos studied in South Africa [5]. The head and the neck is the site most commonly affected and squamous cell carcinoma has been reported to be the commonest skin malignancy seen in albinos [5,20]. Sqamous cell carcinoma arising from actinic keratoses has been reported from India [21]. In the African albino, the risk of developing these malignancies in comparison to the general population has been reported to be as high as up to 1000 fold [22]. 210 © Our Dermatol Online 2.2013
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Volume 4, Number 2, April 2013 ISSN
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Editorial Board: Abdel-Naser Mohame
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CONTENTS E d i t o r i a l O r i g
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Original Article DOI: 10.7241/ourd.
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Figure 1. Survival time of HIV/TB-
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Figure 3. A. melanocytic naevus on
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Page 18 and 19: 82% of the children belonged to the
Page 20 and 21: Comment to the article DOI: 10.7241
Page 22 and 23: The skin around body openings such
Page 24 and 25: Figure 1. Finger nail dystrophy in
Page 28 and 29: Similar type of rash was also prese
Page 30 and 31: 13. Mastaglia FL, Ojeda VJ: Inflamm
Page 32 and 33: Figure 1. Atrophic areas on left up
Page 34 and 35: 5. Brocard A, Quereux G, Moyse D, D
Page 36 and 37: Figure 1. Macroglossia Figure 2. Ma
Page 38 and 39: Case Report DOI: 10.7241/ourd.20132
Page 40 and 41: Figure 4a, b. Skin biopsy shows hyp
Page 46 and 47: Discussion Poikiloderma of Civatte
Page 52 and 53: Case Report A 56 year old Caucasian
Page 54 and 55: Using a battery of neurotoxic agent
Page 56 and 57: Figure 1. Multiple lesions on the u
Page 60 and 61: Figure 1. a PAS positive accentuati
Page 62 and 63: The patient was put on melanocyl 0.
Page 66 and 67: The type of treatment prescribed by
Page 70 and 71: Surgery has been reported to be the
Page 72 and 73: Figure 1. Histological section show
Page 76 and 77: Discussion The breast location of t
Page 78 and 79: Figure 2. The epithelial nests show
Page 82 and 83: Discussion SCACP is one of the cuta
Page 84 and 85: Figure 1. Tumor of the nasal colume
Page 86 and 87: Figure 2. Vesicles and crusts aroun
Page 88 and 89: Outbreaks have occurred recently in
Page 90 and 91: Clasificación En base al epitelio
Page 92 and 93: - Microcefalia, hipoplasia mediofac
Page 94 and 95: Caso Nº 3: · Niña, edad desconoc
Page 96 and 97: Clinical Images DOI: 10.7241/ourd.2
Page 98 and 99: Figure 7. Fixed cutaneous sporotric
Page 100 and 101: Letter to the Editor DOI: 10.7241/o
Page 102 and 103: Historical Article DOI: 10.7241/our
Page 104 and 105: Figure 6. Henri Mondor (1885-1962).
Page 108 and 109: Figure 5. Alfred Guido Miescher (18
Page 112 and 113: Names of ''Lines'', in dermatology
Page 114 and 115: Figure 1. Erik Adolf von Willebrand
Page 116 and 117: THOMAS INMAN English physician, 182
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There are three type of tinea capit
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